Hot cooked foods, such as fried chicken, deep fried fish and seafood, french fried potatoes, pizza and other so called "fast foods" are hot and usually greasy from residual cooking oil. When packaged in conventional containers at the time of sale steam from the hot food cools and condenses, and residual oil and grease draining from the food form pools of moisture (condensate/water) and oil, which makes contact with the food. Consequently, the hot and originally crispy appetizing food often becomes soggy before it is consumed, and less palatable to the buyer. Consumer complaints and lost business can result.
In an effort to overcome the problems associated with packaging hot oily/greasy foods various containers have been developed. While some have been useful in remedying problems of venting steam from hot foods they have not been entirely satisfactory in eliminating sogginess with highly economic disposable packaging. For example, U.S. Pat. 4,797,010 discloses a dual walled insulating bag for packaging fried foods. To prevent sogginess from occurring an inner liner is utilized for absorbing oil/grease from the packaged foodstuff. However, because the liner retains the absorbed grease instead of carrying it away from the foodstuff, portions of the packaged foodstuff remain in contact with the grease/oil soaked liner. Reabsorption of grease/oil by the food can occur through a wicking effect.
U.S. Pat. No. 4,984,907 discloses another type of grease absorbent packaging wherein a porous nonabsorbent liner grid or netting allows for the transmission of grease, fat and oil from the food into an absorbent material positioned between the grid and outer wall of the packaging. Packaging fabricated with inner absorbent materials are often costly to manufacture, and are noneconomic as single use, disposable type bags. U.S. Pat. No. 5,135,787 discloses a further representative example of a food packaging system which relies on an intermediate positioned pad for absorption of liquid during shipping. In order to accommodate the absorbent pad the inner porous bottom wall is elevated from the floor of the package resulting in a substantial trade off in storage capacity. In addition, when the bottom wall of the package is resting on a surface liquid collecting in the bottom compartment may be transferred back to the food compartment. A further representative receptacle which relies on absorbent materials for packaging fluid exuding food products is disclosed by U.S. Pat. No. 4,321,997.
U.S. Pat. No. 3,628,720 discloses a further embodiment of a bag having dual ply walls. However, both the inner liner ply and the outer bag ply have perforations. Such a design would not be suitable for use as a leak proof bag for collecting residual cooking oil and condensate from fried foods. U.S. Pat. No. 4,743,123 also discloses a dual walled bag with offset perforations in both the inner and outer plies. They are employed in packaging powdered products, such as lime, PVC, cocoa, gypsum and cement. The perforated dual plies avoid residual air pockets developing during the filling process.
U.S. Pat. No. 5,132,151 discloses a microwavable packaging system with a multi-ply composite cover having an inner first ply with a plurality of tapered openings in the form of protuberances extending outwardly towards a removable nonporous outer ply. Upon removal of the outer ply, fluids, gases and aromas from the interior of the package are able to escape through the openings in the first ply. Pressure build-up from steam in the container is avoided during the cooking process when the nonporous outer ply is removed. According to U.S. Pat. No. 5,132,151, prior to removal the tapered openings of the porous ply are required to be closed with the nonporous outer ply of film. The intact multi-ply laminated composite would not be suitable for sidewalls of a food container since the blocked openings would prevent transmission of fluids from the interior of the package.
Accordingly, there is a need for more economic packaging for foodstuff, and in particular low cost bags for maintaining cooked foods in a hot, crisp condition after sale, and which avoid sogginess from occurring as a result of the packaged food being in contact with condensing steam and residual oil from the cooking process. Such bags should be leak-proof to liquids and also be capable of mechanically separating steam and oil from the food before it condenses or becomes reabsorbed as it collects on side and bottom walls in the food compartment, all without requiring special absorbent materials, pads, and the like.